KR102172115B1 - Thermosetting resin composition - Google Patents

Abstract

The present invention relates to a thermosetting resin composition containing the following (A) to (D) (A) as a reactant of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups, wherein the SiH group is an alkenyl group. A thermosetting resin containing a group, (B) a straight-chain organopolysiloxane compound having a SiH group only at one end, (C) a silane coupling agent having an epoxy group, (D) a Pt catalyst.

Description

Thermosetting resin composition {THERMOSETTING RESIN COMPOSITION}

The present invention is a thermosetting resin composition comprising a thermosetting resin composed of silsesquioxane and organopolysiloxane having both heat resistance and high refractive index, a cured product obtained by curing the thermosetting resin composition, and an optical semiconductor containing the thermosetting resin composition It provides an optical semiconductor device comprising the composition and the optical semiconductor composition.

White LEDs have been used in applications such as lighting, but heat generation of the LED package has become a problem with the increase in output. In addition, when an epoxy resin is used as a sealing material, yellowing due to heat generation cannot be avoided. Therefore, a silicone resin has been used as a sealing material for white LEDs instead of the epoxy resin. Silicone resins used in LEDs are largely divided into two types: phenyl silicone resin and methyl silicone resin.

Phenyl silicone resins generally used have high refractive index and good light extraction efficiency. In addition, since the gas barrier property is high and the adhesion to the package is good, reliability such as moisture absorption, reflow resistance, heat cycle resistance, and the like are excellent. However, it is superior to the epoxy resin in terms of heat yellowing resistance, but it is not sufficient to cope with the large output of the LED.

Although the methyl silicone resin is very excellent in heat yellowing resistance, since the refractive index is low, the light extraction efficiency of the LED is not good. Further, since the methyl silicone resin is mainly composed of dimethyl silicone, there is a problem in that the gas barrier property is low, the adhesion to the package is inferior, and it is easily peeled off during moisture absorption reflow. When peeling occurs, the luminance of light generated from the LED is lowered, which is not preferable.

In addition, when high-power LEDs appear, particularly when the package size is small, heat is locally filled in the resin portion, causing cracks. In a high-temperature energization test using a high-power LED, the temperature of the resin portion is known to reach a high temperature region of 200°C or higher, and long-term reliability in a higher temperature region is required.

In the high-temperature region, in the phenyl silicone resin generally used, not only the luminance deterioration due to yellowing is severe, but also cracks are generated by the resin deterioration. Although dimethyl silicone resin has little luminance deterioration due to yellowing, in the high-temperature region, the resin progresses, cracks occur, and luminance deteriorates, and may not be applied to the high-power LED use. .

As described above, the characteristics required for an LED encapsulant are becoming more stringent. Accordingly, a sealing material having both high refractive index and heat resistance that can cope with the increase in output of white LEDs, and a thermosetting resin composition having all balances such as moisture absorption reflow resistance or heat cycle resistance are urgently required.

A basket-type silsesquioxane material having excellent heat resistance and UV resistance is attracting attention, and an encapsulant for LEDs using the material has been reported.

Patent Document 1 discloses a sealing agent for LEDs using a thermosetting resin composition of a thermosetting resin in which a SiH group is introduced into a cage-like octasilsesquioxane and an organopolysiloxane having an alkenyl group.

Patent Document 2 discloses a thermosetting resin composition using an incomplete cage silsesquioxane commonly referred to as a double decker type. The silsesquioxane is a compound obtained by hydrolytic condensation of phenyltrimethoxysilane, and since the position of the Si-Ph group is not random and the structure is controlled, it has a high refractive index and has excellent heat resistance and light resistance. .

In Patent Document 2, a thermosetting resin containing a SiH group and a vinyl group obtained from the reaction of a compound obtained by the reaction of an organopolysiloxane having a vinyl group and a compound having a modified SiH group at the silanol base of silsesquioxane having an incomplete cage structure It is disclosed for. Further, it has been shown that curing this thermosetting resin has a high refractive index, high heat resistance, and good adhesion to a polyphthalamide resin substrate or a silver substrate, which is a package material of the LED.

Japanese Patent Application Publication No. 2012-102167 International Publication No. 2011/145638

In Patent Document 1, only the heat resistance at 200°C of the thermosetting resin composition is described, and the properties required for the LED encapsulant such as adhesion to the substrate, heat cycle resistance, and moisture absorption reflow resistance are not described. In addition, since the composition is basically composed of a unit of -Me ₂ Si-O, the refractive index is not high. In addition, the properties of the composition are solid at room temperature, and can be applied to the sealing of LEDs by the molding method, but cannot be applied to the sealing of the LEDs of the dispenser system.

The cured product using a thermosetting resin containing a SiH group and a vinyl group obtained from the reaction of the double-decker type silsesquioxane having four SiH groups described in Patent Document 2 and an organopolysiloxane having two vinyl groups is a double-decker type silsesquioxane. When the quioxane content is small, there is a problem that adhesion performance deteriorates.

In addition, when the content of one silsesquioxane is large, the adhesion performance increases, but the resin may become too hard. As a result, there is a problem that the stress cannot be relieved, and peeling from the LED package occurs in a thermal shock test such as a heat cycle test. In addition, in the package method of the wire bonding type, there is a problem that the wire is easily cut.

The present invention is a thermosetting resin composition having both heat resistance and UV resistance, high refractive index and gas barrier property, low hardness and high adhesion, excellent moisture absorption reflow resistance and heat cycle resistance, and reliability as a sealing agent for LEDs This excellent thermosetting resin composition is provided.

The present inventors have repeatedly studied to solve the above problem. As a result, a thermosetting resin containing a SiH group and an alkenyl group obtained from the reaction of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups, and a straight-chain organopolysiloxane compound having a SiH group only at one end , By incorporating a coupling agent having an epoxy group as an additive, and a Pt catalyst in the thermosetting resin composition, it was possible to reduce the hardness of the cured product without sacrificing high refractive index, heat resistance, and adhesion performance, and the above problems were found to be solved. And came to complete the present invention.

That is, the present invention is as follows.

1. A thermosetting resin composition containing the following (A) to (D).

(A) A thermosetting resin comprising a SiH group and an alkenyl group as a reaction product of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups

(B) a straight-chain organopolysiloxane compound having a SiH group only at one end

(C) Silane coupling agent having an epoxy group

(D) Pt catalyst

2. The thermosetting resin composition according to 1 above, wherein the silsesquioxane is a double decker type silsesquioxane.

3. The thermosetting resin composition according to 1 or 2 above, comprising (E) an organopolysiloxane compound having two or more alkenyl groups as needed.

4. The thermosetting resin composition according to any one of 1 to 3 above, wherein the thermosetting resin (A) is a compound represented by the following formula (1).

[Formula 1]

In formula (1), X is each independently,

It is a group represented by the following formula (XI), formula (X-II) or formula (X-III), and per molecule of the compound represented by formula (1) [the group represented by the formula (XI) and formula ( In the case of a mixture of compounds with different ratios of groups represented by X-II) and groups represented by formula (X-III), the number of groups represented by formula (XI) of the average of 1 molecule of the compound] When the number of groups represented by (X-II) is b and the number of groups represented by formula (X-III) is c, a+2b+c=4, 0<a≤3, 0≤b≤1 And 0<c≤3.

Each R ¹ is independently a group selected from C 1 to C 4 alkyl, cyclopentyl and cyclohexyl, and m is 1 to 100.

[Formula 2]

[Formula 3]

In the formula (X-II), R ² and R ³ are each independently a group selected from C 1 to C 4 alkyl, cyclopentyl, cyclohexyl and phenyl, and r is -OSi(R ³ ) _2- It is a repetition number, and r is an average value satisfying 2-20. R ¹ is the same as R ¹ in the formula (1).

[Formula 4]

In the formula (X-III), R ⁴ and R ⁵ are each independently a group selected from C 1 to C 4 alkyl, cyclopentyl, cyclohexyl and phenyl, and s is -OSi(R ⁵ ) _2- It is a repetition number, and s is an average value satisfying 2-20.

5. The thermosetting resin composition according to any one of 1 to 4 above, wherein the straight-chain organopolysiloxane compound (B) having a SiH group only at the one end is a compound represented by the following formula (2).

[Formula 5]

In the above formula (2), R ⁶ and R ⁷ are each independently a group selected from alkyl, cyclopentyl and cyclohexyl having 1 to 4 carbon atoms, and m'is a repeat of -OSi(R ⁷ ) _2- It is a number, and it is an average value satisfying 1-20.

6. The thermosetting resin composition according to any one of 3 to 5 above, wherein the organopolysiloxane compound (E) having two or more alkenyl groups is a compound represented by the following formula (3).

[Formula 6]

In formula (3), R ⁸ and R ⁹ are each independently a group selected from C 1 to C 4 alkyl, cyclopentyl, cyclohexyl, and phenyl, and n is a repeat of -OSi(R ⁹ ) _2- It is a number, and it is an average value satisfying 1-50.

7. Based on the total amount of the thermosetting resin composition, the blending ratio of the thermosetting resin (A) is 70 to 95% by mass, the organopolysiloxane compound (B) is 2 to 20 mass%, and the silane coupling agent The thermosetting resin composition according to any one of 1 to 6 above, wherein the blending ratio of (C) is 0.1 to 5.0 mass%.

8. The thermosetting resin composition according to any one of the above 3 to 7, further containing the organopolysiloxane compound (E) in a proportion of 1 to 10% by mass as necessary.

9. The thermosetting resin composition in any one of said 1-8 further containing at least one of silica and a phosphor.

10. A cured product obtained by curing the thermosetting resin composition according to any one of 1 to 9 above.

11. An optical semiconductor composition containing the thermosetting resin composition in any one of said 1-9.

12. An optical semiconductor device comprising the composition for optical semiconductors according to 11 above as a sealing agent.

The cured product obtained by curing the thermosetting resin composition of the present invention can have a high refractive index, high heat resistance, and maintain excellent adhesion properties, while lowering the hardness of the cured product. Therefore, the cured product sealed by the thermosetting resin composition of the present invention has excellent stress relaxation ability, and the optical semiconductor device manufactured using the thermosetting resin composition can withstand stringent reliability tests such as heat cycle resistance test. It becomes an optical semiconductor device. In addition, it is an optical semiconductor device having low hardness, low surface tackiness, possible dicing, and excellent moldability.

Since the thermosetting resin composition of the present invention has a silsesquioxane skeleton as a main component, the cured product is excellent in heat resistance and UV resistance. In addition, it exhibits excellent adhesion to a housing substrate such as polyphthalamide resin, silver or ceramics, and can withstand stringent reliability tests such as moisture absorption reflow or heat cycle tests.

The excellent properties of the thermosetting resin composition of the present invention are that the organopolysiloxane compound having only a SiH group at one end of the present invention is an incomplete cage-type silsesquioxane thermosetting resin having a main SiH group and an alkenyl group. By reacting with a kenyl group, the crosslinking density can be suppressed, and as a result, it becomes a low hardness capable of stress relaxation, and the organopolysiloxane compound having a SiH group at one end binds only one end of the organopolysiloxane, and the degree of freedom Is high, and is believed to be due to not changing the physical properties of the cured resin itself.

In the following, the present invention will be described in detail.

The thermosetting resin composition of the present invention is characterized by containing the following (A) to (D).

(A) A thermosetting resin comprising a SiH group and an alkenyl group as a reaction product of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups

(B) a straight-chain organopolysiloxane compound having a SiH group only at one end

(C) Silane coupling agent having an epoxy group

(D) Pt catalyst

Hereinafter, each component will be described.

(A) A thermosetting resin comprising a SiH group and an alkenyl group as a reaction product of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups

The thermosetting resin (A) is a reaction product of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups.

Examples of silsesquioxanes having a SiH group include double-decker silsesquioxanes and cage silsesquioxanes having a T8 structure. While the T8 structure of the cage silsesquioxane has eight functional groups, the double-decker type silsesquioxane used in the present invention has only four functional groups, making it easy to control the structure.

In addition, unlike the fully condensed cage silsesquioxane, the double decker type silsesquioxane preferably used in the present invention is an incomplete condensation type, has a relatively high degree of freedom of the molecule, and has excellent flexibility. From this point of view, a double decker type silsesquioxane is preferable.

As a thermosetting resin (A), there exists a compound represented by following formula (1), for example.

[Formula 7]

In formula (1), each of the following X is independently a group represented by the following formula (XI), formula (X-II), or formula (X-III). Each R ¹ is independently a group selected from C 1 to C 4 alkyl, cyclopentyl and cyclohexyl, and m is 1 to 100. Especially, as for m, 1 is preferable.

[Formula 8]

[Formula 9]

In formula (X-II), R ² and R ³ are each independently a group selected from alkyl having 1 to 4 carbon atoms, cyclopentyl, cyclohexyl, and phenyl, and preferably methyl. r is the repetition number of -OSi(R ³ ) ₂ -, and r is an average value satisfying 2 to 20. As for r, 2-10 are more preferable. R ¹ is the same as R ¹ in the formula (1).

[Formula 10]

In the formula (X-III), R ⁴ and R ⁵ are each independently a group selected from C 1 to C 4 alkyl, cyclopentyl, cyclohexyl and phenyl, and s is -OSi(R ⁵ ) _2- It is a repetition number, and s is an average value satisfying 2-20. As for s, 2-10 are preferable and 2-4 are more preferable.

Per 1 molecule of the compound represented by formula (1) [The compound is a mixture of compounds having different ratios of groups represented by formula (XI), groups represented by formula (X-II), and groups represented by formula (X-III) In the case of, the number of groups represented by formula (XI) in the formula (XI) of the compound 1 molecule] is a, the number of groups represented by formula (X-II) is b, and the group represented by formula (X-III) When the number is c, a+2b+c=4, 0<a≤3, 0≤b≤1, and 0<c≤3.

In the present invention, a compound in a range satisfying a+2b+c=4, 0<a≤3, 0≤b≤1, and 0<c≤3 will be described.

The compound represented by the general formula (1) is a>c, has a larger number of SiH groups than vinyl groups on average, and can be defined as a so-called SiH type thermosetting resin. From the viewpoint of remarking excellent properties when a is formed into a cured product, a is preferably 1.0 to 3.0, and more preferably 1.3 to 2.5.

In the compounds represented by the general formula (1), a, b, and c can be adjusted by the inventors, for example, by conforming to the production method described in International Publication No. 2011/145638.

The thermosetting resin composition of the present invention preferably contains 70 to 95% by mass of the thermosetting resin (A), and more preferably 80 to 90% by mass, based on the total amount of the thermosetting resin composition. By setting the blending ratio of the thermosetting resin (A) to 70% by mass or more, it is possible to maintain the properties of the double decker silsesquioxane, that is, properties such as heat resistance, UV resistance, and high refractive index. Moreover, by making the blending ratio of the thermosetting resin (A) 95 mass% or less, the hardness of a cured product can be D 45 or less.

(B) a straight-chain organopolysiloxane compound having a SiH group only at one end

As the straight-chain organopolysiloxane compound (B) having a SiH group only at one end, a compound represented by the following formula (2) is exemplified.

[Formula 11]

In the above formula (2), R ⁶ and R ⁷ are each independently a group selected from alkyl, cyclopentyl and cyclohexyl having 1 to 4 carbon atoms, and among them, a methyl group having 1 carbon number or a carbon number of 4 The butyl group of is preferred. m'is the number of repetitions of -OSi(R ⁷ ) ₂ -. m'is an average value satisfying 4-20, and it is preferable that it is an average value satisfying 4-15. It is more preferable that it is an average value satisfying 5-10.

The organopolysiloxane compound (B) can be produced by a known and common method. For example, it can be synthesized by the method described in JP 2000-273178 A or JP 2001-055446 A.

The organopolysiloxane compound (B) is used in order to lower the hardness. That is, by reacting with the alkenyl group of the thermosetting resin (A) to lower the overall crosslinking density, an increase in hardness can be suppressed, and thus the hardness can be reduced.

The content of the organopolysiloxane compound (B) in the thermosetting resin composition of the present invention is preferably a content in which the refractive index of the cured product obtained by curing the thermosetting resin composition is 1.5 or more. In addition, if too small, the hardness is not lowered, so it is preferable that the content of the cured product is D 40 or less.

It is preferable that it is 148-2000, and, as for the number average molecular weight of the organo polysiloxane compound (B), it is more preferable that it is 400-1000. When the number average molecular weight of the organopolysiloxane compound (B) is 400 or less, a number average molecular weight of 400 or more is more preferable because volatility is high and there is a risk of starting to occur in the step of blending and curing the curing composition. Further, by setting the number average molecular weight of the organopolysiloxane compound (B) to 2000 or less, as a reaction product of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups, a thermosetting resin containing a SiH group and an alkenyl group The compatibility with and can be maintained, transparency of a cured product can be maintained, and adhesion performance can be maintained.

The blending ratio of the organopolysiloxane compound (B) is preferably 5 to 20% by mass, and more preferably 5 to 15% by mass in the total thermosetting resin composition of the present invention. By setting the blending ratio of the organopolysiloxane compound (B) to 5% by mass or more, it is possible to lower the hardness of the cured product to D45 or less. Further, by setting the blending ratio of the organopolysiloxane compound (B) to 20% by mass or less, it is possible to effectively obtain a cured product of low hardness while maintaining various properties such as heat resistance, UV resistance, and adhesion of the cured product.

(C) Coupling agent having an epoxy group

As a silane coupling agent (C) having an epoxy group, for example, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyl Dimethoxysilane, 3-glycidoxypropyltriethoxysilane and 3-glycidoxypropylmethyldiethoxysilane. Among these, 3-glycidoxypropyltrimethoxysilane is more preferable.

The blending ratio of the silane coupling agent (C) is preferably 0.1 to 5.0 mass%, and more preferably 0.2 to 2 mass%, in the total thermosetting resin composition of the present invention. Moreover, it is more preferable to set it as 0.25 mass%-1.0 mass %. By setting the blending ratio of the silane coupling agent (C) to 0.1% by mass or more, the wettability of the curable resin to the LED package substrate is increased, and heat cycle resistance can be maintained. Further, by setting the blending ratio of the silane coupling agent (C) to 5.0% by mass or less, it is possible to maintain heat resistance.

(D) Pt catalyst

The Pt catalyst (D) is a catalyst containing platinum, and the platinum may not be oxidized or may be oxidized. As oxidized platinum, there is, for example, platinum oxide. Partly oxidized platinum is, for example, Adams' catalyst.

Examples of the Pt catalyst include Karstedt catalyst, Speier catalyst and hexachloroplatinic acid. These are generally well-known catalysts. Among these, a non-oxidized type of Karsted catalyst is preferable.

The blending ratio of the Pt catalyst (D) in the total thermosetting resin composition of the present invention is preferably an amount sufficient to advance the curing of the curable resin composition of the present invention, specifically, it is preferably 0.01 ppm to 10 ppm. It is more preferable to set it as 0.1 ppm-1 ppm. It is possible to advance curing by setting the blending ratio of the Pt catalyst (D) to 0.01 ppm or more. It is possible to accelerate curing by setting the blending ratio of the Pt catalyst (D) to 0.1 ppm or more. Further, it is possible to maintain the heat resistance of the cured product by setting the blending ratio of the Pt catalyst (D) to 10 ppm or less.

(E) Organopolysiloxane compound having two or more alkenyl groups

The thermosetting resin composition of the present invention may further contain (E) an organopolysiloxane compound having two or more alkenyl groups, if necessary. As the organopolysiloxane compound (E) having two or more alkenyl groups, a compound represented by the following general formula is exemplified.

[Formula 12]

In the formula (3), R ⁸ and R ⁹ are each independently a group selected from alkyl, cyclopentyl, cyclohexyl and phenyl having 1 to 4 carbon atoms, and n is -OSi(R ⁹ ) _2- It is a repetition number and is an average value satisfying 1-50.

The organopolysiloxane compound (E) is a component for adjusting the viscosity of the cured composition of the present invention or for aiding strength or flexibility to a cured product. In the above formula (3), when both R ⁸ and R ⁹ are alkyl having 1 to 4 carbon atoms, methyl having 1 carbon atom is preferably used, and is represented by the following general formula (4).

[Formula 13]

In the above formula (4), n'is an average value satisfying 1 to 20. When n'exceeds 20, compatibility with the cured composition of the present invention deteriorates, which is not preferable. In the sense of imparting flexibility, 5 or more are preferable, and 10 or less are preferable from the viewpoint of gas barrier properties. From the viewpoint of flexibility and gas barrier properties, 5 to 8 are particularly preferred.

Further, in the above formula (3), a compound represented by the following general formula (5) or (6) in which at least a part of R ⁸ and R ⁹ is a phenyl group can also be preferably used.

[Formula 14]

In said formula (5), x is an average value satisfying 1-50, Preferably it is 1-20.

[Formula 15]

In the above formula (6), y+z is an average value that satisfies 1 to 50, and a value that satisfies y/(y+z)<0.5 is preferable from the viewpoint of refractive index and gas barrier properties. In the meaning of imparting flexibility to the cured product, it is preferable that y+z is 10 or more.

These organopolysiloxane compounds (E) having two or more alkenyl groups may be used in combination at the discretion of the inventor.

The organopolysiloxane compound (E) can be produced by a known and common method. Specifically, for example, the organopolysiloxane compound represented by formula (4) is subjected to equilibration reaction of tetramethylvinyldisiloxane and octamethylcyclotetrasiloxane in the presence of a solid acid catalyst such as activated clay, and then by filtration. It can be produced by removing the solid acid catalyst and then cutting at a low boiling point under vacuum conditions of about 0.13 kPa and temperature conditions of 100 to 120°C.

In addition, for example, the organopolysiloxane compound represented by formula (5) or formula (6) can be produced by a known and common method. In addition, the organopolysiloxane compound represented by Formula (5) or Formula (6) can be obtained industrially from GELEST.

The compounding ratio of the organopolysiloxane compound (E) is preferably 10% by mass or less in the total thermosetting resin composition of the present invention. Heat resistance is improved and resin strength is increased by making the compounding ratio of the organopolysiloxane compound (E) 10% by mass or less, which is preferable.

The thermosetting resin composition of the present invention may further contain the following components.

i) Hardening retardant

As the curing retarding material, a known material used as an addition type curable composition using a hydrosilylation catalyst can be used. Specifically, for example, there are compounds containing two or more alkenyl groups, compounds containing aliphatic unsaturated bonds, organic phosphorus compounds, tin-based compounds, and organic peroxides. These may be used alone, or two or more types may be used in combination.

Examples of the compound containing two or more alkenyl groups include vinyl group-containing cyclic siloxanes such as disiloxanes and trisiloxanes containing both terminal vinyl groups, and 1,3,5,7-tetravinyltetramethylcyclotetrasiloxane. There is Ryu.

As a compound containing an aliphatic unsaturated bond, for example, 3-methyl-1-dodecin-3-ol, 3,5-dimethyl-1-hexin-3-ol, 1-ethynyl-1-cyclohexanol And maleic acid esters such as propargyl alcohols, en-phosphorus compounds, maleic anhydride and dimethyl maleate.

Examples of organophosphorus compounds include triorganophosphines, diorganophosphines, organophosphones and triorganophosphites.

Examples of tin compounds include stannous halide dihydrate and stannous carboxylic acid. Further, examples of the organic peroxide include di-tert-butyl peroxide, dicumyl peroxide, benzoyl peroxide, and tert-butyl perbenzoate.

Among these, 1,3-divinyldisiloxane, 1,3,5,7-tetravinyltetramethylcyclotetrasiloxane or 1-ethynyl-1-cyclohexanol is preferable.

By blending the curing retardant to the thermosetting resin composition of the present invention, an increase in viscosity at room temperature can be suppressed and pot life can be obtained. The content of the curing retardant in the thermosetting resin composition of the present invention is preferably 0.001 to 0.1% by mass, and more preferably 0.01 to 0.05% by mass.

ii) phosphor

It has a light-emitting function by dispersing a phosphor in the thermosetting resin composition of the present invention, and can be used as a composition for LEDs. The content of the phosphor in the thermosetting resin composition of the present invention is preferably 1 to 90% by mass, and more preferably 2 to 50% by mass.

There is no limitation on the phosphor that can be used in the thermosetting resin composition of the present invention. Further, the concentration distribution of the phosphor in the composition may be uniform or may be different. The type of phosphor to be used, the presence or absence of a concentration distribution of the phosphor, and conditions for the distribution may be determined according to the usage environment, use, and purpose of the LED.

iii) silica

To the thermosetting resin composition of the present invention, silica may be added for the purpose of improving the resin strength or preventing the precipitation of the phosphor. The ratio of silica in the thermosetting resin composition of the present invention is preferably 1 to 10% by weight with respect to the total amount of the thermosetting resin composition.

Silica may be a silica produced by fine-grained (natural silica) produced in nature, or industrially synthesized silica (synthetic silica) may be used. In the case of natural silica, since it is a crystal, it has a crystal axis. Therefore, although optical characteristics derived from crystals can be expected, since the specific gravity is slightly higher than that of synthetic silica, dispersion in the thermosetting resin composition may be affected. In addition, when obtained by pulverizing a natural product, there are cases in which it becomes particles of an irregular shape or a material with a wide particle size distribution.

Synthetic silica includes wet synthetic silica and dry synthetic silica, but the use of the synthetic silica is not particularly limited in the present invention. However, synthetic silica may have crystal water regardless of the manufacturing method, and if the crystal water has the potential to have any effect on the thermosetting resin composition or cured product, or the LED device, it is recommended to select the number of crystal water in consideration. desirable.

Synthetic silica is not crystal but amorphous, and therefore does not have a crystal axis, and optical characteristics derived from crystals cannot be expected very much. However, it is possible to control the particle distribution, and in addition, features such as being able to make the particle diameter extremely small can be utilized.

In particular, fumed silica has a nano-order particle diameter and is excellent in particle dispersibility. In addition, in the case of comparison by the same weight, the smaller the particle diameter, the larger the total surface area, and thus the reflection direction of light becomes more diverse, and thus it can be used more preferably.

In general, silica has a large surface area and is a hydrophilic material (hydrophilic silica) due to the effect of silanol present on the surface, but it can also be made of hydrophobic silica by chemical modification. Which type of silica to use is selected depending on the purpose, but in the present invention, it is preferable to use hydrophilic silica for experimental verification.

The method for producing the thermosetting resin composition of the present invention is not particularly limited, and for example, a homo disper, a homo mixer, a universal mixer, a planetary mixer, a kneader, a triaxial roll or beads There is a method of mixing predetermined amounts of the above-described curing retardant, silicone resin, and, if necessary, the above-described thermal curing agent, antioxidant, and the like, using a mixer such as a mill, at room temperature or under heating.

The use of the thermosetting resin composition or the cured product thereof of the present invention is not particularly limited, but for example, a light emitting device of an optical semiconductor device such as a sealant, a housing material, a die bonding material for connection to a lead electrode or a heat sink, etc. It can be used as an underfill material in the case of flip chip mounting, and as a passivation film on a light emitting element. Among them, since an optical semiconductor device capable of efficiently extracting light by light emission from an optical semiconductor element can be manufactured, it can be preferably used as a sealing agent, an underfill material, or a die bonding material.

As conditions for obtaining a cured product by curing the thermosetting resin composition of the present invention by heating, the temperature is preferably 60 to 200°C, and more preferably 80 to 160°C. In addition, the time is preferably 1 to 24 hours, more preferably 2 to 5 hours.

It is preferable that the hardness of the hardened|cured material obtained by hardening|curing the thermosetting resin composition of this invention is a range of D hardness 45 or less and A hardness 30 or more. Further, the refractive index is preferably a high refractive index of 1.5 or more. When the refractive index is 1.5 or more, it becomes a cured product excellent in light extraction efficiency of the LED.

The method of sealing a light-emitting element with the composition for optical semiconductors of the present invention is not particularly limited, for example, a lead frame in which the composition for optical semiconductors of the present invention is injected in advance into a molded frame, and the light-emitting element is fixed thereto ( There are a method of curing after immersing a lead frame), and a method of injecting and curing the composition for an optical semiconductor of the present invention into a mold frame in which a light emitting element is inserted.

As a method of injecting the composition for an optical semiconductor of the present invention, for example, there are injection by a dispenser, transfer molding, and injection molding. In addition, as other sealing methods, for example, a method of dropping the composition for optical semiconductors of the present invention onto a light-emitting element and applying and curing through a stencil printing, screen printing, and a mask, and There is a method of injecting and curing the composition for an optical semiconductor of the present invention into a cup on which a light-emitting element is disposed.

An optical semiconductor device comprising the composition for an optical semiconductor device of the present invention as a sealing agent is also one of the present invention.

Example

The present invention will be described in more detail based on examples. In addition, the present invention is not limited by the following examples.

(A) A thermosetting resin comprising a SiH group and an alkenyl group as a reaction product of a silsesquioxane having a SiH group and an organopolysiloxane having two alkenyl groups

As a thermosetting resin containing a SiH group and an alkenyl group, which is a component (A) of the present invention, the following silsesquioxane derivative base polymer 1 and silsesquioxane prepared by the method disclosed in International Publication No. 2011/145638 Derivative base polymer 2 was used.

[Silsesquioxane derivative base polymer 1]

In the formula (1), a [formula (XI)] = 2.34, 2b [formula (X-II)] = 0, c [formula (X-III)] = 1.66, a compound represented by the following formula It was set as silsesquioxane derivative base polymer 1.

[Formula 16]

[Silsesquioxane derivative base polymer 2]

In the formula (1), a [formula (XI)] = 2.37, 2b [formula (X-II)] = 0.48, c [formula (X-III)] = 1.14, a compound represented by the following formula It was set as the silsesquioxane derivative base polymer 2.

[Formula 17]

<Measurement of number average molecular weight>

The number average molecular weight of the polymer synthesized in the present invention was measured as follows. Using a high-performance liquid chromatography system CO-2065plus manufactured by Japan Spectroscopy Co., Ltd., 20 μL of a THF solution having a sample concentration of 1% by mass was used as an analysis sample, and a column: Shodex KF804L [manufactured by Showa Electric Corporation] (serial Furnace two connections), column temperature: 40°C, detector: RI, eluent: THF, and eluent flow rate: 1.0 mL per minute, measured by the GPC method, and calculated in terms of polystyrene.

(B) a straight-chain organopolysiloxane compound having a SiH group only at one end

As the organo polysiloxane having a SiH group only at one end, which is the component (B) of the present invention, a single-ended SiH silicon manufactured by JNC Corporation and having a number average molecular weight of 900 or 500 was used. In addition, as a comparative compound for component (B), SiH silicon at both ends of a number average molecular weight of 500 was used.

The organopolysiloxane having a SiH group only at one end and having a number average molecular weight of 900 and 500 was prepared by referring to the method described in Japanese Laid-Open Patent Publication No. 2000-273178. In addition, the SiH silicon at both terminals having a number average molecular weight of 500 was prepared by referring to a method described in Japanese Patent Laid-Open No. 2003-252995.

[Single-ended SiH silicon with number average molecular weight of 900]

In the formula (2), a compound represented by the following formula, wherein R ⁶ =butyl, R ⁷ =methyl, m =11, was used as a single-ended SiH silicone having a number average molecular weight of 900.

[Formula 18]

[Single-ended SiH silicon with number average molecular weight of 500]

In the formula (2), a compound represented by the following formula, wherein R ⁶ =butyl, R ⁷ =methyl, m =5, was used as a single-ended SiH silicone having a number average molecular weight of 500.

[Formula 19]

[SiH silicon at both ends of number average molecular weight 500]

As a comparative component of the component (B) of the present invention, SiH silicon at both terminals having a number average molecular weight of 500 represented by the following formula was used.

[Formula 20]

(C) Silane coupling agent having an epoxy group

As the silane coupling agent which is the component (C) of the present invention, glycidyl ether trimethoxysilane: registered trademark Sila Ace S510 (manufactured by JNC Corporation) was used.

(D) Pt catalyst

As the Pt catalyst which is the component (D) of the present invention, a 3wt% xylene solution (manufactured by Yumicore) was used as the Karstead catalyst brand name Pt-VTS.

(E) organopolysiloxane having two or more alkenyl groups

The organopolysiloxane compound having two or more alkenyl groups as component (E) of the present invention is a compound represented by the following formula in formula (3), wherein R ⁸ =methyl, R ⁹ =methyl, n =8 The number average molecular weight was made into the vinyl silicone at both ends of 700.

[Formula 21]

<Preparation of thermosetting resin composition>

The compound synthesized in the above example or a mixture of organopolysiloxane was put in the screw tube. The screw tube was set in a rotation/revolution mixer ("Awadori Rental (registered trademark)" ARE-250 manufactured by Shinki Co., Ltd.), and mixing and defoaming were performed.

The Karsted catalyst (brand name Pt-vtx: a xylene solution having a Pt concentration of 3%) prepared by Umicore was used as a curing retardant: MVS-H (brand name, 1,3,5,7-tetravinyl-1,3, 5,7-tetramethylcyclotetrasiloxane (manufactured by JNC Co., Ltd.) was added to a predetermined amount of Pt, followed by mixing and defoaming with a rotation/revolution mixer, and compositions a to e as thermosetting resin compositions, and Comparative compositions f to h and j were obtained. Table 1 shows the blending amount (g) of each thermosetting resin composition.

<Preparation of a composition containing a filler>

In the above thermosetting resin composition, silica was dispersed as a filler to obtain compositions cs1 and cs2. Table 3 shows the blending amount (g) of the filler-containing composition.

Silsesquioxane derivative base polymer 1, a single-ended SiH silicone having a molecular weight of 900, S510, and silica were prepared in nano-dispersed silica by using a triaxial roll mill according to the mixing ratio shown in Table 3.

Thereafter, both terminal vinyl silicones and Pt catalysts having a molecular weight of 700 were mixed and degassed again by a rotation/revolution mixer according to the blending ratio shown in Table 3 to obtain compositions as1 to as3 as thermosetting resin compositions. Table 3 shows the blending amount (g) of each thermosetting resin composition.

And the silica used is as follows.

Silica I: fumed silica hydrophilic type average primary particle diameter 7 nm

Product name: Aerozil #300 manufactured by Japan Aerozil

Silica II: fumed silica hydrophilic type average primary particle diameter of 12 nm

Product name: Leorosil QS102 manufactured by Tokuyama Co., Ltd.

<Production of hardened cargo>

The thermosetting resin composition was sandwiched between two sheets of glass with Naflon SP packing (4 mm diameter) manufactured by Nichias Co., Ltd. as a spacer, and the thermosetting resin composition was poured therein, followed by degassing under reduced pressure at 80°C. It cured by heating at 150°C for 1 hour and then in the order of 4 hours, and the glass was peeled off to obtain cured products a to e and comparative cured products f to h and j with a smooth surface having a thickness of 4 mm.

About the obtained hardened|cured material a-e and comparative hardened|cured material f-h and j, its physical properties were evaluated by the following method. The results are shown in Table 2.

<viscosity>

The viscosity of the cured product was measured using a TV-22 type viscometer cone plate type manufactured by Toki Industries Co., Ltd. at a constant temperature of 25°C.

<Light transmittance>

A cured product having a thickness of 4 mm was prepared, and the transmittance of light at a wavelength of 400 nm was measured with an ultraviolet-visible spectrophotometer UV-1650 manufactured by Shimadzu Corporation.

<Heat-resistant transmittance>

The heat resistance test was performed and evaluated by the following method. A cured product having a thickness of 4 mm was prepared, and the transmittance of light at a wavelength of 400 nm was measured with an ultraviolet-visible spectrophotometer UV-1650 manufactured by Shimadzu Corporation, and it was set as the initial transmittance. The cured product was placed in an oven at 180°C (fixed temperature dryer: DX302 manufactured by Yamato Scientific Co., Ltd.) and heated for a certain period of time (1000 hours in Table 2).

The light transmittance of the cured product after the heat resistance test was measured with an ultraviolet-visible spectrophotometer, and the retention at this wavelength (transmittance after heat treatment for a certain time/initial transmittance at each wavelength × 100) was calculated and evaluated from the transmittance at a wavelength of 400 nm. When the transmittance retention rate at 400 nm after 1000 hours of the 180°C heat resistance test was 85% or more, it was set as ?, and when it was 75% or more, it was set as?

<UV transmittance resistance>

UV transmittance is irradiation of 550 to 600 mW/cm ² through a band pass filter of 365 nm using a deep UV lamp manufactured by Ushio Co., Ltd. on a 4 mm thick cured product. UV irradiation was performed by intensity. If the retention rate at 400 nm after irradiation for 2000 hours was 99% or more, it was set as ?, and if it was 97% or more, it was set as?

<refractive index>

As for the test piece, the cured product was cut with a band saw, and a test piece was prepared according to JIS K7142 (2008). Using this test piece, the refractive index was measured using an Abbe refractometer (manufactured by Atago Co., Ltd., NAR-2T) using the D line (586 nm) of a sodium lamp. Methylene iodide was used as the intermediate solution.

<hardness>

According to the regulations of JIS K6253 (2006), the D hardness is measured by the durometer WR-105D manufactured by Nishi-Tokyo Precision Co., Ltd., and the A hardness is durometer WR- manufactured by Nishi-Tokyo Precision Co., Ltd. Measured by 104A.

<Adhesive>

The surface of the sample was touched with a finger to check the adhesion of the surface of the cured product. The case where there is no adhesiveness and the finger slips on the sample surface was set as "○", the case where there was a slight grip feeling was set as "△", and the case where there was a sticky feeling was set as "×".

<Adhesion strength test PPA>

The test was performed according to JIS K6850 (1999). The test piece was prepared by adjusting the dimensions of a polyphthalamide resin (manufactured by Solvay Advanced Polymers Co., Ltd., submodel (brand name) A-4122NLWH905) as a base material according to JIS K6850 (1999), and a thermosetting resin composition between them. It was sandwiched and prepared by heating and curing at 80°C for 1 hour and then at 150°C for 1 hour. The adhesion test was measured using a 5 kN load cell by a tensile compression tester (manufactured by Shimadzu Corporation, Autograph AGS-500B).

<Agglomeration destruction>

With respect to the fracture surface of the test body when the shear adhesive strength was measured in the adhesive strength test PPA, in the case of cohesive failure, it was set as the interface in the case of cohesion and interfacial peeling. In addition, cohesive failure refers to the fact that the cured product of the substrate and the composition did not peel off at the interface and the cured product itself is fractured, and it means that there is adhesion to the substrate. The thing in which cohesive failure and interfacial peeling were mixed was set as cohesion/interface.

<Adhesion strength test PA9T>

The test was performed according to JIS K6850 (1999). The test piece was prepared by adjusting the dimensions of a polyphthalamide resin (manufactured by Craray Co., Ltd., Genesta (brand name) PA9T) as a base material according to JIS K6850 (1999), and sandwiching a thermosetting resin composition between them. It was produced by heating and curing at 1 hour at C and then at 150 C for 1 hour. The adhesion test was measured using a 5 kN load cell with a tensile compression tester [manufactured by Shimadzu Corporation, Autograph AGS-500B].

<Agglomeration destruction>

With respect to the fracture surface of the test body when the shear adhesion strength was measured in the adhesive strength test PA9T, in the case of cohesive failure, it was set as the interface in the case of cohesion and interfacial peeling. Incidentally, cohesive failure refers to the fact that the cured product of the substrate and the composition did not interfacially peel, and the cured product itself is broken, and it means that there is adhesiveness with the substrate. The thing in which cohesive failure and interfacial peeling were mixed was set as cohesion/interface.

<Water vapor transmittance>

The test was performed according to JIS Z0208. For the test piece, a cured product having a thickness of 0.9 mm was prepared, and the cured product was mounted and fixed in a 70 mm diameter cup covered with calcium chloride as a moisture absorbing material, and weighed every 24 hours under conditions of 40°C and humidity of 90 RH. The increment was measured. And, the effective area is 28.26 cm ² . The water vapor permeability was calculated|required by the following formula.

Water vapor transmittance (g/m ² /24h)=240×{(Gross weight of the test body after the moisture permeability test (g)-(Gross weight of the test body before the moisture permeability test (g)}×/28.26)

<Moisture absorption reflow test>

A thermosetting resin composition is injected into 16 PPA resin packages for power LEDs with silver-plated bottom edge [manufactured by Enomoto Co., Ltd., model number 5050 D/G] with a dispenser (manufactured by Musashi Corporation, model number MPP-1) Then, it was heat-cured under conditions of 80°C for 1 hour and 150°C for 4 hours. These PPA resin packages were subjected to moisture absorption in an environmental tester (manufactured by SPEC, model number SH-241) at a temperature of 30° C., a relative humidity of 60%, and a moisture absorption condition of 192 hours, and then a simulated reflow machine [Malcolm ( Note) The reflow furnace was passed twice under the temperature condition (260°C) according to the JEDEC standard according to [Manufacture, Model No. SRS-1C]. The number of peelings and cracks out of 16 are shown.

<Reflow/heat cycle test>

After injecting a thermosetting resin composition into 16 PPA resin packages for power LEDs with silver-plated bottoms [manufactured by Enomoto Co., Ltd., model number 5050 D/G] with a dispenser (manufactured by Musashi Co., Ltd., model number MPP1), 80℃ for 1 hour, It was heat-cured under conditions of 150°C and 4 hours. These PPA resin packages were subjected to reflow once by a simulated reflow machine [Malcolm Co., Ltd. product, model number SRS-1C] under a temperature condition (260°C) conforming to the JEDEC standard. Thereafter, it was put in the test area of the cold and thermal shock device [manufactured by SPEC Co., Ltd., model number TSE-11], exposed at -40°C for 30 minutes, and exposed at 105°C for 30 minutes as 1 cycle, and repeated 500 cycles. Implemented. And, the transfer time between both exposure temperatures was carried out for 2 minutes. Peeling and occurrence of cracks were observed under a microscope. It shows the defective rate out of 15.

[Table 1]

[Table 2]

[Table 3]

[Table 4]

As shown in Table 2, the cured products a to e using the compositions a to e of the present invention have a hardness in the range of D 45 or less to A 30, and the refractive index is 1.5 or more, and is excellent in heat resistance and UV resistance. And, it was found that the adhesion to the polyphthalamide resin (PPA, PA9T) was also good, and the moisture absorption reflow resistance and heat resistance were excellent.

On the other hand, the comparative cured product f using the comparative composition f not using the organopolysiloxane compound having only one end of the SiH group had high adhesion, but was too hard and had no heat cycle resistance. In addition, the hardness of the comparative cured product g using the comparative composition g only decreased to D45. Moreover, heat resistance deteriorated. The comparative cured product h using the comparative composition h had a low hardness of A hardness of 66, but the heat resistance and UV resistance were also deteriorated, and the adhesion was also deteriorated.

The comparative cured product j using the comparative composition j was excellent in hardness, heat resistance, UV resistance and adhesion of D hardness of 30, but was inferior in moisture absorption reflow resistance and heat cycle resistance.

As shown in Table 4, the composition of the present invention in which silica is dispersed also has a hardness in the range of D 45 or less to A 30, the refractive index of 1.5 or more, and adhesion to polyphthalamide resins (PPA, PA9T). It was also found that the moisture absorption reflow resistance and heat resistance resistance were excellent. In addition, this composition is a nano-dispersed silica, can prevent sedimentation of the phosphor, efficiently extracts light, and contributes to reducing color unevenness.

Although the present invention has been described in detail using a specific aspect, it is clear to those skilled in the art that various changes and modifications can be made without departing from the intention and scope of the present invention. In addition, this application is based on the Japanese patent application (Japanese Patent Application No. 2012-232847) for which it applied on October 22, 2012, The whole is used by reference.

[Industrial availability]

The thermosetting resin composition of the present invention has high heat resistance, high UV resistance, high adhesion to a substrate, and excellent toughness, and thus provides a cured product having excellent moisture absorption reflow resistance and heat cycle resistance. It is very useful as a sealing agent for optical semiconductor devices such as LEDs.

Claims (12)

Thermosetting resin composition containing the following (A) to (D):
(A) a thermosetting resin represented by the following formula (1),
(B) a straight-chain organopolysiloxane compound having a SiH group only at one end,
(C) a silane coupling agent having an epoxy group,
(D) Pt catalyst

In the above formula (1), X is each independently,
It is a group represented by the following formula (XI), formula (X-II) or formula (X-III), and per molecule of the compound represented by formula (1) [the group represented by the formula (XI) and formula ( In the case of a mixture of compounds with different ratios of groups represented by X-II) and groups represented by formula (X-III), the number of groups represented by formula (XI) of the average of 1 molecule of the compound] When the number of groups represented by (X-II) is b and the number of groups represented by formula (X-III) is c,
a+2b+c=4, 0<a≤3, 0≤b≤1, 0<c≤3,
R ¹ is each independently a group selected from C 1 to C 4 alkyl, cyclopentyl and cyclohexyl, m is 1 to 100,

In the above formula (X-II), R ² and R ³ are each independently a group selected from alkyl having 1 to 4 carbon atoms, cyclopentyl, cyclohexyl, and phenyl, and r is -OSi(R ³ ) _2- Is the repetition number of, r is an average value satisfying 2 to 20, R ¹ is the same as R ¹ in the above formula (1)

In the above formula (X-III), R ⁴ and R ⁵ are each independently a group selected from alkyl, cyclopentyl, cyclohexyl and phenyl having 1 to 4 carbon atoms, and s is -OSi(R ⁵ ) _2- It is the repetition number of, and s is an average value satisfying 2-20. The method of claim 1,
(E) A thermosetting resin composition further comprising an organopolysiloxane compound having two or more alkenyl groups. The method of claim 1,
The thermosetting resin composition, wherein the straight-chain organopolysiloxane compound (B) having a SiH group only at the one end is a compound represented by the following formula (2):

R ⁶ and R ⁷ are each independently a group selected from C 1 to C 4 alkyl, cyclopentyl and cyclohexyl, m'is a repeating number of -OSi(R ⁷ ) ₂ -, and satisfying 1 to 20 This is the average value. The method of claim 2,
The thermosetting resin composition, wherein the organopolysiloxane compound (E) having two or more alkenyl groups is a compound represented by the following formula (3):

In the formula (3), R ⁸ and R ⁹ are each independently a group selected from alkyl, cyclopentyl, cyclohexyl and phenyl having 1 to 4 carbon atoms, and n is -OSi(R ⁹ ) _2- It is the number of repetitions, and is an average value satisfying 1-50. The method of claim 1,
Based on the total amount of the thermosetting resin composition, the blending ratio of the thermosetting resin (A) is 70 to 95 mass%, the organopolysiloxane compound (B) is blended at 2 to 20 mass%, and the silane coupling agent (C ), the thermosetting resin composition is 0.1 to 5.0 mass%. The method according to claim 2 or 4,
A thermosetting resin composition containing the organopolysiloxane compound (E) in a proportion of 1 to 10% by mass. The method according to any one of claims 1 to 5,
A thermosetting resin composition further containing at least one of silica and a phosphor. A cured product obtained by curing the thermosetting resin composition according to any one of claims 1 to 5. The composition for optical semiconductors containing the thermosetting resin composition in any one of Claims 1-5. An optical semiconductor device comprising the composition for optical semiconductors according to claim 9 as a sealing agent. delete delete